Lua-尝试调用全局（nil值）

Bone = class(function(b, id, xp)
    b.id = id
    b.xp = xp
end)

function forId(bid) 
    local xp = 0.0
    if bid == 526 or bid == 528 or bid == 2530 or bid == 2859 then
        xp = 4.5
    elseif bid == 3179 or bid == 3180 or bid == 3183 or bid == 3185 then
        xp = 5.0
    elseif bid == 530 then
        xp = 53
    elseif bid == 532 or bid == 3125 then
        xp = 15
    elseif bid == 4812 then
        xp = 22.5
    elseif bid == 7839 then
        xp = 30
    elseif bid == 6812 then
        xp = 50
    elseif bid == 536 then
        xp = 72
    end
    local bone = Bone:new(bid, xp)
    return bone
end

function execute(args)
    local itemid = 526
    local bone = forId(itemid) -- this is where the error occurs
end

module

local forId = forId //or _G.forId
local bone = forId(itemid)

dofile(core.app_path() .. \"\\\\strategies\\\\standard\\\\include\\\\helper.lua\");